I saw the thread about best resistance bands- my question is do they work? How do they work the muscle differently? Isn't pumping iron with free weights the best because it simulates what muslces really do?

Tue. Mar 10, 6:46pm

"The natural principle of elastic resistance is to get more difficult as the elastic is stretched. This means that your muscles will get more resistance at the optimum point during the exercise. The ultra expensive and large gym machines are designed with the same principles in mind.

Also remember, all weights (dumbbell, barbell, plate, rock) are limited to the principles of gravity. In other words, the resistance is straight up and down."

"A critical benefit of elastic resistance is that it prevents the user from “cheating” on the exercise being performed6. This is a common practice, especially for beginners, when using free weights. Cheating involves the use of momentum to get the weight moving.

Once the weight has built up momentum, the muscle fibers do not need to be maximally activated to continue moving the weight throughout the rest of the range of motion of the exercise. This is due to the fact that the physics of momentum have taken over to move the weight.

The physical properties of elastic resistance devices do not allow the user to cheat by using momentum. This is because the resistance from the elastic equipment comes from the stretching of the elastic material and not the mass of the elastic equipment. The only way to continue a movement while performing an exercise with elastic resistance is to utilize more muscle fibers in the exercising muscle to continue stretching the elastic material. "

"Another reason linear variable resistance, as provided by elastic resistance, is beneficial is due to what is known as the strength curve of muscles. The linear variable resistance provided by elastic tubing better mimics the strength curves of most muscles. A strength curve refers to the way a muscle’s or muscle group’s strength changes over a range of motion. Because of their anatomy, most muscles increase in strength over the range of motion until a certain point. Again using the biceps curl as an example, as you curl the hand toward the shoulder, the muscle gets stronger up until about the halfway point of the range of motion. Thus, the biceps muscle is weakest at the start of the exercise and strongest at the halfway point of the exercise. When doing a biceps curl with a free weight, the individual is limited to how much resistance he can use by how strong the biceps are at the beginning of the exercise (its weakest point). That means that during the biceps curl, the muscle is not receiving adequate resistance when the muscle is in its strongest point in the range of motion. When performing a curl with elastic tubing, however, the resistance increases as the range of motion increases. This means the muscle is receiving greater resistance at its strongest point in the range of motion and therefore is receiving more adequate resistance to better stimulate strength adaptations."